| 摘要 |
The present invention relates to a cardiac assist apparatus comprising: a blood pump (10) electrically connected to a drive unit-electric motor and to a frequency sensor (24) for sensing rotation rate of the blood pump (10). The drive unit-electric motor (12) is electrically connected to a power supply unit (14). A current sensor (20) senses an average direct current waveform of the drive unit-electric motor (12). A power supply voltage sensor (22) senses the power supply unity (14) voltage. A microprocessor (18), being electrically connected to the blood pump (10), receives data from the frequency sensor (24), the current sensor (20), and the power supply voltage sensor (22). A method of controlling blood flow through the above-described blood pump (10) is characterized by the following steps of: sensing a current waveform of the drive unit-electric motor (12) of the blood pump; sensing an input voltage waveform to the drive unit-electric motor (12); sensing a rotational frequency waveform of the drive unit-electric motor (12). In the microprocessor, there is passively determined at least one of the following data, and namely drive unit-electric motor (12) input power in order to determine flow rate through the blood pump (10), a patient heart rate, current pump flow rate, and systemic pressure wherein the determination is carried out without influencing the performance of the blood pump (10) of patient’s physiology. The microprocessor (18) then calculates a desired flow rate proportional to the patient heart rate and subsequently the operation of the blood pump (10) is adjusted to a required flow rate. |
